Frederick III (king of Denmark and Norway)
Frederick III, 1609–70, king of Denmark and Norway (1648–70), son and successor of Christian IV. He at first made great concessions to the powerful nobles but later asserted his own power. In 1657 war with Sweden began anew. Charles X of Sweden forced Denmark to accept the humiliating Treaty of Roskilde (1658). Charles soon renewed the war, and it was only through the heroic defense of Copenhagen by Frederick, assisted by Dutch ships, that the Danish kingdom was saved from utter destruction. The Netherlands and Brandenburg, allies of Denmark, then assisted in repulsing the Swedes, and the peace of Copenhagen was made (1660). Denmark lost Skåne, Halland, and Blekinge to Sweden. Denmark was devastated and in debt. To help the country recover, the burghers and clergy united to end aristocratic power and privilege. The monarchy was declared hereditary, and the state administration was centralized and staffed by civil servants. A constitution granting absolute power to a hereditary monarch was published after Frederick's death (see Griffenfeld). Frederick was succeeded by his son, Christian V.